Older Xcode compatibility!

Clocker/Onboarding/OnboardingParentViewController.swift

@@ -69,10 +69,9 @@ class OnboardingParentViewController: NSViewController {
         [negativeButton, backButton].forEach { $0?.isHidden = true }
 
         if #available(OSX 10.16, *) {
-            negativeButton.controlSize = .large
-            positiveButton.controlSize = .large
-            backButton.image = NSImage(systemSymbolName: "chevron.left.circle.fill",
-                                       accessibilityDescription: nil)
+//            negativeButton.controlSize = .large
+//            positiveButton.controlSize = .large
+            backButton.image = Themer.shared().symbolImage(for: "chevron.left.circle.fill", "back-button")
         } else {
             backButton.title = NSLocalizedString("Back",
                                                  comment: "Button title for going back to the previous screen")

Clocker/Overall App/Themer.swift

@@ -152,8 +152,7 @@ extension Themer {
 
     func shutdownImage() -> NSImage {
         if #available(macOS 10.16, *) {
-            return NSImage(systemSymbolName: "ellipsis.circle",
-                           accessibilityDescription: nil)!
+            return symbolImage(for: "ellipsis.circle", nil)
         }
 
         if #available(macOS 10.14, *) {
@@ -172,8 +171,7 @@ extension Themer {
 
     func preferenceImage() -> NSImage {
         if #available(macOS 10.16, *) {
-            return NSImage(systemSymbolName: "gear",
-                           accessibilityDescription: nil)!
+            return symbolImage(for: "gear", nil)
         }
 
         if #available(macOS 10.14, *) {
@@ -195,8 +193,7 @@ extension Themer {
 
     func pinImage() -> NSImage {
         if #available(macOS 10.16, *) {
-            return NSImage(systemSymbolName: "macwindow.on.rectangle",
-                           accessibilityDescription: nil)!
+            return symbolImage(for: "macwindow.on.rectangle", nil)
         }
 
         if #available(macOS 10.14, *) {
@@ -320,8 +317,7 @@ extension Themer {
 
     func sharingImage() -> NSImage {
         if #available(macOS 10.16, *) {
-            return NSImage(systemSymbolName: "square.and.arrow.up.on.square.fill",
-                           accessibilityDescription: nil)!
+            return symbolImage(for: "square.and.arrow.up.on.square.fill", nil)
         }
 
         if #available(macOS 10.14, *) {
@@ -448,4 +444,10 @@ extension Themer {
             NSColor(deviceRed: 241.0 / 255.0, green: 241.0 / 255.0, blue: 241.0 / 255.0, alpha: 1.0) :
             NSColor(deviceRed: 42.0 / 255.0, green: 55.0 / 255.0, blue: 62.0 / 255.0, alpha: 1.0)
     }
+
+    func symbolImage(for _: String, _: String?) -> NSImage {
+        // Dummy image for older xcodes
+        return NSImage(named: NSImage.Name("Calendar Tab Icon"))!
+//    return NSImage(systemSymbolName: name, accessibilityDescription: accessibilityDescription)!
+    }
 }

Clocker/Panel/ParentPanelController.swift

@@ -168,7 +168,7 @@ class ParentPanelController: NSWindowController {
         showDebugVersionViewIfNeccesary()
 
         if #available(macOS 10.16, *) {
-            mainTableView.style = .fullWidth
+//            mainTableView.style = .fullWidth
         }
     }
 

Clocker/Panel/UI/TimezoneDataSource.swift

@@ -135,8 +135,7 @@ extension TimezoneDataSource: NSTableViewDataSource, NSTableViewDelegate {
             })
 
             if #available(OSX 10.16, *) {
-                swipeToDelete.image = NSImage(systemSymbolName: "trash.fill",
-                                              accessibilityDescription: nil)
+                swipeToDelete.image = Themer.shared().symbolImage(for: "trash.fill", "Trash Button")
             } else {
                 swipeToDelete.image = NSImage(named: NSImage.Name("Trash"))
             }